Method and system for promoting adhesion of arc-spray coatings

ABSTRACT

Methods to promote adhesion of coatings on surfaces, such as promoting adhesion of arc-spray coatings or thermal-spray coatings onto surfaces such as metallic or ceramic surfaces. The method applies a non-thermal plasma stream at atmospheric pressure to an article surface, creating an energized surface region that promotes adhesion of an arc-spray coating. In one aspect, the arc-spray coating is applied onto a metallic or ceramic surface.

FIELD

The present invention is directed to a method to promote adhesion ofcoatings on surfaces, such as promoting adhesion of arc-spray orthermal-spray coatings onto surfaces such as metallic or ceramicsurfaces with use of a non-thermal plasma stream at atmosphericpressure.

BACKGROUND

Arc-spray or thermal spray coatings are frequently applied to articlesurfaces. Traditionally, the surface to receive the arc-spray coatingmust be prepared to ensure adequate adhesion of the arc-spray coating.For example, surfaces are commonly roughened by way of grit blasting tocreate a surface more amenable to bonding to the arc-spray coating. Suchsurface preparation processes may be complicated, costly, andinconsistent. Using grit or media blasting requires that the user has asufficient supply of correctly sized and shaped particulates to create auniform blasted surface profile or texture. The blast media is oftenonly useable once before it becomes contaminated or is fractured uponimpact rendering the media ineffective for a second application. Themedia presents an ongoing source of dusts and the spent abrasive mediamust be disposed of. The disclosure eliminates or drastically reducesthe need to use blast media to prepare the surface prior to arc-spraycoating. A method of surface pre-treatment applied to an article thatuniformly and predictably enhances the bonding of an arc-spray coatingis needed.

Conventional approaches to applying an arc-spray coating to a surface orincreasing the adherence of a surface prior to application of anarc-spray coating include: U.S. Pat. No. 4,578,310 to Hatfield.incorporated by reference in entirety. Plasma systems have been used toprepare a surface but are traditionally vacuum plasma systems or variousatmospheric plasma systems such as a corona, dielectric barrierdischarge, and downstream plasma systems, such as: U.S. Pat. No.5,913,144 to Nguyen, E. P. patent application Ser. No. 0,265,765 toChan, and U.S. Pat. Appl. No. 2010/0237043 to Garlough, each of whichare incorporated by reference in entirety. Some systems and methodsdescribe removal of materials from substrates using an atmosphericplasma source, such as U.S. Pat. No. 8,133,324 to Claar, U.S. Pat. No.8,981,251 to Yancey, and U.S. Pat. No. 8,604,379 to Yancey, each ofwhich are incorporated by reference in entirety. WIPO 2017/087991 toYancey describes a method and device to promote adhesion of metallicsurfaces, incorporated by reference in entirety.

What is needed is a method to provide effective and efficient bonding ofan arc-spray coating, or a thermal spray coating, to an article. Thedisclosure solves this need. The disclosure provides a method to promoteadhesion of coatings on surfaces. More specifically, the disclosuredescribes the use of a non-thermal plasma stream at atmospheric pressureto promote adhesion of arc-spray coatings, or thermal spray coatings,onto surfaces such as metallic or ceramic surfaces. In one embodiment,both the article and the arc-spray are metallic. Some benefits of themethod are the elimination of the need to grit blast surfaces prior toapplying an arc spray coating and creating a stronger and more uniformbond between the coating and the article surface.

SUMMARY

The present disclosure can provide several advantages depending on theparticular aspect, embodiment, and/or configuration.

The disclosure involves methods to promote adhesion of coatings onsurfaces, such as promoting adhesion of arc-spray coatings, or thermalspray coatings, onto surfaces such as metallic or ceramic surfaces withuse of a non-thermal plasma stream at atmospheric pressure. Generally,the method applies a non-thermal plasma stream at atmospheric pressureto an article surface, creating an energized surface region thatpromotes adhesion of a coating, such as an arc-spray coating or athermal spray coating. In one aspect, the coating is applied onto ametallic or a ceramic surface.

In one embodiment, a method to adhere an arc-spray coating to a surfaceof an article is disclosed, the method comprising: generating anon-thermal plasma stream, the non-thermal plasma stream at atmosphericpressure; positioning the surface of the article to receive thenon-thermal plasma stream; treating the surface of the article with thenon-thermal plasma stream to create an energized surface region;generating an arc-spray coating stream; directing the arc-spray coatingstream at the energized surface region; wherein: the arc-spray coatingstream forms an arc-spray coating surface associated with the energizedsurface region of the article.

In one aspect, the energized surface region comprises etched organicresidues. In another aspect, the non-thermal plasma stream provides achemical etching and cleaning of the substrate. In another aspect, thenon-thermal plasma stream comprises monatomic oxygen species. In anotheraspect, the article is metallic, and the surface is a metallic surface.In another aspect, wherein the energized surface region is a metal oxideregion. In another aspect, the metal oxide region comprises an outeroxide surface. In another aspect, the arc-spray coating stream isdirected at the outer oxide region. In another aspect, the article ismetallic, the surface comprises a metallic surface, and the arc-spraystream comprises a metal.

In one aspect, the method further comprises the step of forming chemicalbonding sites on the energized surface region, the chemical siteschemically bonding with the metal of the arc-spray stream. In anotheraspect, the article is metallic, and the surface is a metallic surface,and the method further comprises the step of heating the article. In oneaspect, the method further comprises the step of applying an auxiliarygas onto the surface of the article. In one aspect, the non-thermalplasma stream comprises monatomic nitrogen. In one aspect, the arc-spraycoating stream is a metallic arc-spray coating stream comprising astream of projected molten metal surrounded by a sheath of air plasma.In one aspect, the surface is a metallic surface, and the non-thermalplasma stream comprises an energetic species chemically reactive withthe metallic surface. In one aspect, the method further comprisesapplying a gas curtain associated with the non-thermal plasma stream. Inone aspect, the arc-spray stream comprises a sheath of air plasma.

In one aspect, the method further comprises the step of forming chemicalbonding sites on the energized surface region, the chemical bondingsites promoting chemical bonding with the energized surface region. Inone aspect, the article is metallic, and the surface is a metallicsurface. In one aspect, the method further comprises the step ofapplying an auxiliary gas onto the surface of the article. In oneaspect, the non-thermal plasma stream comprises monatomic nitrogen. Inone aspect, the arc-spray coating stream is a metallic arc-spray coatingstream comprising a stream of projected molten metal surrounded by asheath of air plasma. In one aspect, the surface is a metallic surface,and the non-thermal plasma stream comprises an energetic specieschemically reactive with the metallic surface. In one aspect, theenergized surface region comprises etched inorganic residues. In oneaspect, the article is ceramic, the surface comprises a ceramic surface,and the arc-spray stream comprises a metal. In one aspect, the articleis ceramic, the surface comprises a ceramic surface, and the arc-spraystream comprises a cermet. In one aspect, the article is ceramic, thesurface comprises a ceramic surface, and the arc-spray stream comprisesa ceramic. In one aspect, the non-thermal plasma stream comprisesmonatomic chemical species. In one aspect, the non-thermal plasma streamcomprises a tailored gas that forms a tailored chemical species on thesurface. In one aspect, the tailored gas is ammonia and the tailoredchemical species comprise amine groups. In one aspect, the tailored gasis water and the tailored chemical species comprise hydroxyl groups.

In another embodiment, a method to bond an arc-spray coating to a metalsurface of an article is disclosed, the method comprising: generating anon-thermal plasma stream, the non-thermal plasma stream at atmosphericpressure and comprising monatomic oxygen (and/or other atomic andmolecular species); positioning the metal surface of the article toreceive the non-thermal plasma stream; treating the metal surface of thearticle with the non-thermal plasma stream to create a metal oxideregion, the metal oxide region comprising an outer oxide surface andetched organic residues; generating a metallic arc-spray coating streamcomprising a stream of projected molten metal surrounded by a sheath ofair plasma; and directing the metallic arc-spray coating stream at themetal oxide region; wherein: the molten metal bonds with the metal oxideregion to bond the arc-spray coating to the metal surface of thearticle.

In yet another embodiment, a system to adhere an arc-spray coating to asurface of an article is disclosed, the system comprising: a plasmagenerating device configured to generate a non-thermal plasma stream atatmospheric pressure; and an arc-spray generating device configured togenerate an arc-spray coating stream; wherein: the non-thermal plasmastream is directed at the surface of the article to create an energizedsurface region; the arc-spray coating stream is directed at theenergized surface region; and the arc-spray coating is adhered to thesurface of the article.

In one aspect, the non-thermal plasma stream comprises monatomic oxygen,the article is metallic with a metallic surface, and the arc-spraystream comprises a metal. In another aspect, the non-thermal plasmagenerating device is configured to direct an auxiliary gas onto themetallic surface, and the arc-spray coating stream is a metallicarc-spray coating stream comprising a stream of projected molten metalsurrounded by a sheath of air plasma.

The word “plasma” generally refers to an ionized gas comprising amixture of charged species (ions and electrons), metastable(electronically excited) species, and neutral species; the volume ofmatter in the plasma state additionally emits photons. For convenience,unless specified otherwise or the context dictates otherwise, the word“plasma” encompasses not only fully active (actively generated) plasmabut also partially extinguished plasma and afterglow, to the extent thata partially extinguished plasma or an afterglow has properties(composition of species, energy level, etc.) effective for implementingthe methods disclosed herein.

The phrases “non-thermal plasma, “non-equilibrium” plasma, and “cold”plasma generally refers to a plasma exhibiting low temperature ions andneutral species (relative to a “thermal” plasma) and high electrontemperatures relative to the temperature of the surrounding gas. Anon-thermal plasma is distinguished from a thermal plasma in that athermal plasma exhibits a higher overall temperature and energy densitywith both high electron temperatures and high ion and neutraltemperatures.

The word “generating” in the context of generating plasma refers to theinitial step of striking (creating) the plasma from a plasma-precursorgas (or mixture of gases) and also sustaining (maintaining) the plasmaafter the plasma has been struck. A plasma will be sustained as long asthe conditions required for sustaining the plasma are maintained, suchas an input of electrical (or electromagnetic) power with theappropriate operating parameters (e.g., voltage, frequency, etc.), asufficient source of, plasma- precursor gas etc.

The phrase “atmospheric pressure,” such as used the context of“atmospheric pressure plasma,” is not limited to a precise value ofpressure corresponding exactly to sea-level conditions. For instance,the value of “atmospheric pressure” is not limited to exactly 1 atm.Instead, “atmospheric pressure” generally encompasses ambient pressureat any geographic location and thus may encompass a range of values lessthan and/or greater than 1 atm as measured at sea level. Generally, an“atmospheric pressure plasma” is one that may be generated in an open orambient environment, i.e., without needing to reside in apressure-controlled chamber or evacuated chamber, although a chamber (ator around atmospheric pressure), may be utilized to confine the plasmato maintain a desired chemical environment, such as excluding oxygen toprevent oxidation.

The word “substrate” generically refers to any structure that includes asurface on which an adhesion-promoting oxide layer may be formed inaccordance with the present disclosure. The substrate may present asurface having a simple planar or curved geometry or may have a complexor multi-featured topography.

The phrase “metallic substrate” refers to a substrate composed of asingle metal or a metal alloy. Such a substrate is not necessarily pure,in that a trace amount of impurities may exist in its lattice structure.

The phrase “metal oxide” or “metal nitride,” depending on the type ofoxide or nitride, generally may refer a stoichiometric or non-stoichiometric formulation of the oxide or nitride. As one non-limitingexample, “titanium oxide” may encompass stoichiometric titanium oxide,typically but not exclusively titanium dioxide (T1O2), and/or TiO_(Y),where y ranges from 0.7-2. A mixture of stoichiometric metal oxide (ornitride) and non- stoichiometric metal oxide (or nitride) may be presentin a layer of metal oxide (or nitride) formed in accordance with thepresent disclosure.

The word “nanoscale” refers to a dimension (e.g., thickness) on theorder of nanometers (nm). A nanoscale dimension is typically one that isless than 1000 nm, i.e., less than 1 micrometer (μm).

The phrase “arc-spray” as used in the phrase “arc-spray coating” or“arc-sprayed coating” means a sprayed molten metal propelled by a gas,such as propelled by compressed air via atomization, applied as asurface coating.

The phrase “thermal spray” means as used in the phrase “thermal spraycoating” or “thermal-sprayed coating” means a sprayed coating comprisinga heat source and a coating in a molten form that is propelled toward asubstrate to form a coating of the molten material.

The phrase “energized surface region” means an elevated surface energyfrom a nominal surface energy, as typically measured by dyne level (adyne meaning 10 micronewtons or 10 E-5 newtons).

The phrase “etched organic residue” means an organic remainder that hasbeen embedded into a surface.

The phrase “auxiliary gas” means a gas that is complementary to aprimary gas, such as ammonia, water, nitrogen, a combination of an inertgas with a reactive gas, a combination of different gases that createsspecific ionization state such as Penning ionization mixture, an inertgas. The primary gas may be composed primarily of oxygen or air.

The phrase “energetic species” means any unstable compound, such as anionized gas, a neutral gas that is unstable, or any chemical constituentnot in an equilibrium state at given temperature and pressure.

The phrases “gas curtain” means a gas stream that surrounds, encircles,or exists adjacent another stream, such as a gas curtain of oxygen thatsurrounds a stream of molten metal.

The word “sheath” such as used in the phrase “sheath of air plasma”means a formation that surrounds, encircles, or exists adjacent astream, such as a sheath of air surrounding a stream of molten metal.

The phrase “molten metal” means metal that has been heated to atemperature above its melting point and is in the liquid state.

The phrase “monatomic” such as used in the phrase “monatomic oxygen”means consisting of one atom in a material.

The phrase “organic coating” means a typically carbonaceous coating thatdepends primarily on its chemical inertness and impermeability to form alayer or coating onto a surface, to include primers, adhesive cementsand topcoats such as enamel, varnish and paints.

These and other advantages will be apparent from the disclosure of theinventions contained herein. The above-described embodiments,objectives, and configurations are neither complete nor exhaustive. Aswill be appreciated, other embodiments of the invention are possibleusing, alone or in combination, one or more of the features set forthabove or described in detail below. Further, this Summary is neitherintended nor should it be construed as being representative of the fullextent and scope of the present invention, nor its uses. The presentinvention is set forth in various levels of detail in this Summary, aswell as in the attached drawings and the detailed description below, andno limitation as to the scope of the present invention is intended toeither the inclusion or non-inclusion of elements, components, etc. inthis Summary. Additional aspects of the present invention will becomemore readily apparent from the detailed description, particularly whentaken together with the drawings, and the exemplary claims providedherein.

The phrases “at least one”, “one or more”, and “and/or” are open-endedexpressions that are both conjunctive and disjunctive in operation. Forexample, each of the expressions “at least one of A, B and C”, “at leastone of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B,or C” and “A, B, and/or C” means A alone, B alone, C alone, A and Btogether, A and C together, B and C together, or A, B and C together.

The term “a” or “an” entity refers to one or more of that entity. Assuch, the terms “a” (or “an”), “one or more” and “at least one” can beused interchangeably herein. It is also to be noted that the terms“comprising”, “including”, and “having” can be used interchangeably.

The term “automatic” and variations thereof, as used herein, refers toany process or operation done without material human input when theprocess or operation is performed. However, a process or operation canbe automatic, even though performance of the process or operation usesmaterial or immaterial human input, if the input is received beforeperformance of the process or operation. Human input is deemed to bematerial if such input influences how the process or operation will beperformed. Human input that consents to the performance of the processor operation is not deemed to be “material”.

The term “computer-readable medium” as used herein refers to any storageand/or transmission medium that participate in providing instructions toa processor for execution. Such a computer-readable medium is commonlytangible, non-transitory, and non-transient and can take many forms,including but not limited to, non-volatile media, volatile media, andtransmission media and includes without limitation random access memory(“RAM”), read only memory (“ROM”), and the like. Non-volatile mediaincludes, for example, NVRAM, or magnetic or optical disks. Volatilemedia includes dynamic memory, such as main memory. Common forms ofcomputer-readable media include, for example, a floppy disk (includingwithout limitation a Bernoulli cartridge, ZIP drive, and JAZ drive), aflexible disk, hard disk, magnetic tape or cassettes, or any othermagnetic medium, magneto-optical medium, a digital video disk (such asCD-ROM), any other optical medium, punch cards, paper tape, any otherphysical medium with patterns of holes, a RAM, a PROM, and EPROM, aFLASH-EPROM, a solid state medium like a memory card, any other memorychip or cartridge, a carrier wave as described hereinafter, or any othermedium from which a computer can read. A digital file attachment toe-mail or other self-contained information archive or set of archives isconsidered a distribution medium equivalent to a tangible storagemedium. When the computer-readable media is configured as a database, itis to be understood that the database may be any type of database, suchas relational, hierarchical, object-oriented, and/or the like.Accordingly, the disclosure is considered to include a tangible storagemedium or distribution medium and prior art-recognized equivalents andsuccessor media, in which the software implementations of the presentdisclosure are stored. Computer-readable storage medium commonlyexcludes transient storage media, particularly electrical, magnetic,electromagnetic, optical, magneto-optical signals.

Moreover, the disclosed methods may be readily implemented in softwareand/or firmware that can be stored on a storage medium to improve theperformance of: a programmed general-purpose computer with thecooperation of a controller and memory, a special purpose computer, amicroprocessor, or the like. In these instances, the systems and methodscan be implemented as program embedded on personal computer such as anapplet, JAVA® or CGI script, as a resource residing on a server orcomputer workstation, as a routine embedded in a dedicated communicationsystem or system component, or the like. The system can also beimplemented by physically incorporating the system and/or method into asoftware and/or hardware system, such as the hardware and softwaresystems of a communications transceiver.

Various embodiments may also or alternatively be implemented fully orpartially in software and/or firmware. This software and/or firmware maytake the form of instructions contained in or on a non-transitorycomputer-readable storage medium. Those instructions may then be readand executed by one or more processors to enable performance of theoperations described herein. The instructions may be in any suitableform, such as but not limited to source code, compiled code, interpretedcode, executable code, static code, dynamic code, and the like. Such acomputer-readable medium may include any tangible non-transitory mediumfor storing information in a form readable by one or more computers,such as but not limited to read only memory (ROM); random access memory(RAM); magnetic disk storage media; optical storage media; a flashmemory, etc.

The terms “determine”, “calculate” and “compute,” and variationsthereof, as used herein, are used interchangeably and include any typeof methodology, process, mathematical operation or technique.

The term “means” as used herein shall be given its broadest possibleinterpretation in accordance with 35 U.S.C., Section 112, Paragraph 6.Accordingly, a claim incorporating the term “means” shall cover allstructures, materials, or acts set forth herein, and all of theequivalents thereof. Further, the structures, materials or acts and theequivalents thereof shall include all those described in the summary,brief description of the drawings, detailed description, abstract, andclaims themselves.

The term “module” as used herein refers to any known or later developedhardware, software, firmware, artificial intelligence, fuzzy logic, orcombination of hardware and software that can perform the functionalityassociated with that element.

The preceding is a simplified summary of the disclosure to provide anunderstanding of some aspects of the disclosure. This summary is neitheran extensive nor exhaustive overview of the disclosure and its variousaspects, embodiments, and/or configurations. It is intended neither toidentify key or critical elements of the disclosure nor to delineate thescope of the disclosure but to present selected concepts of thedisclosure in a simplified form as an introduction to the more detaileddescription presented below. As will be appreciated, other aspects,embodiments, and/or configurations of the disclosure are possibleutilizing, alone or in combination, one or more of the features setforth above or described in detail below. Also, while the disclosure ispresented in terms of exemplary embodiments, it should be appreciatedthat individual aspects of the disclosure can be separately claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like elements. The elements of the drawingsare not necessarily to scale relative to each other. Identical referencenumerals have been used, where possible, to designate identical featuresthat are common to the figures.

FIG. 1 is a flowchart depicting one embodiment of a method to promoteadhesion of a surface coating to an article;

FIG. 2A is a schematic elevation view of an article to receive a surfacecoating consistent with the method of FIG. 1;

FIG. 2B is a schematic elevation view of the article of FIG. 2A afterapplication of a non-thermal plasma stream to a surface of the article;

FIG. 2C is a schematic elevation view of the article of FIG. 2B afterapplication of an arc-spray coating to a surface of the article; and

FIG. 3 is a block diagram of an embodiment of a system to promoteadhesion of a surface coating to an article.

It should be understood that the proportions and dimensions (eitherrelative or absolute) of the various features and elements (andcollections and groupings thereof) and the boundaries, separations, andpositional relationships presented there between, are provided in theaccompanying figures merely to facilitate an understanding of thevarious embodiments described herein and, accordingly, may notnecessarily be presented or illustrated to scale, and are not intendedto indicate any preference or requirement for an illustrated embodimentto the exclusion of embodiments described with reference thereto.

DETAILED DESCRIPTION

Reference will now be made in detail to representative embodimentsillustrated in the accompanying drawings. While various embodiments ofthe present invention have been described in detail, it is apparent thatmodifications and alterations of those embodiments will occur to thoseskilled in the art. However, it is to be expressly understood that suchmodifications and alterations are within the scope and spirit of thepresent invention. Further, the inventions described herein are capableof other embodiments and of being practiced or of being carried out invarious ways. In addition, it is to be understood that the phraseologyand terminology used herein is for the purposes of description andshould not be regarded as limiting. The use of “including,”“comprising,” or “adding” and variations thereof herein are meant toencompass the items listed thereafter and equivalents thereof, as wellas, additional items.

The following disclosure generally relates to methods and systems topromote adhesion of coatings on surfaces, such as promoting adhesion ofarc-spray or thermal-spray coatings onto surfaces such as metallic orceramic surfaces with use of a non-thermal plasma stream at atmosphericpressure.

Additional details of the invention are provided in the attached figuresand/or tables. With attention to FIG. 1, a flowchart depicting oneembodiment of a method 100 to promote adhesion of a surface coating toan article is depicted. The description of the method 100 of FIG. 1 willreference elements of FIGS. 2A-C, which depicts three schematicelevation views of an article 200 receiving a surface coating consistentwith the method of FIG. 1, and to FIG. 3, which depicts a system 300 topromote adhesion of a surface coating to an article 200.

Generally, the method 100 applies a non-thermal plasma stream 410 atatmospheric pressure to an article surface 208, creating an energizedsurface region that promotes adhesion of an arc-spray coating.

The non-thermal plasma stream 410 at atmospheric pressure increases thesurface energy of a metallic or ceramic surface which in turn increasesthe bonding of an arc sprayed metallic surface coating. The non-thermalplasma stream 410 is used as a bonding adhesion promoter that enhancesthe adhesion of arc-sprayed coating layers, thereby enabling smoothsurfaces with little roughness to be coated with an arc spray coatingwith improved adhesion.

The arc-spray coating is applied to the energized region. In oneembodiment, both the article and the arc-spray are metallic.

Generally, the system 300 to promote adhesion of a surface coating to anarticle comprises a plasma generating device 400 and an arc-spraygenerating device 500 (or a thermal spray generating device). Each ofthe plasma generating device 400 and an arc-spray generating device 500emit a stream directed at a surface 208 of an article 200. In oneembodiment, both the article and the arc-spray are metallic. In anotherembodiment, the arc-spray may be a ceramic, a mixture of a ceramic and ametal (termed a CERMET) In another embodiment, the arc-spray may be asemiconductor, or other material that can be liquefied and sprayed inits molten state to impact on a surface that is at a temperature that isbelow the melting point of the material being sprayed, such that whenthe molten/liquid spray impacts the surface it is cooled to atemperature that is lower than the melting point of the liquefiedmaterial and solidifies onto the surface forming a coating.

The method 100 starts at step 104 and ends at step 128. Any of thesteps, functions, and operations discussed herein can be performedcontinuously and automatically. In some embodiments, one or more of thesteps of the method 100 may comprise computer control, use of computerprocessors, and/or some level of automation. The steps are notionallyfollowed in increasing numerical sequence, although, in someembodiments, some steps may be omitted, some steps added, and the stepsmay follow other than increasing numerical order.

After starting at step 104, at step 108 a non-thermal plasma stream 410,at atmospheric pressure, is generated by a plasma generating device 400.Any of several means may be used to generate the non-thermal plasmastream at atmospheric pressure, to include by use of the devices andmethods described in the previously-identified patent documents: U.S.Pat. No. 8,981,251 to Yancey, U.S. Pat. No. 8,604,379 to Yancey, andWIPO 2017/087991 to Yancey (collectively, the “Yancey techniques.”)

In one embodiment, the non-thermal plasma stream 410 is provided by aplasma generating device 400 configured to discharge an atmosphericpressure plasma stream (or plasma “plume”) 410 from a nozzle. The plasmagenerating device 400 may be positioned at some specified distancebetween the nozzle and the surface of the article 200, and oriented todirect the atmospheric pressure non-thermal plasma stream 410 toward thesurface 208 of the article 200. While the atmospheric pressurenon-thermal plasma stream 410 is active, the nozzle directink theatmospheric pressure non-thermal plasma stream 410 device may be movedacross the surface 208 of the article 200.

The non-thermal plasma stream 410 and/or the plasma generating device400 may be configured with any combination of the following parameters.Generally, the operating parameters associated with the plasmagenerating device 400 to generate the non-thermal plasma stream 410 areselected to produce a stable plasma discharge. The operating parametersmay vary depending on the composition of the metallic substrate 204(i.e., the type of metal or metal alloy) on (from) which the energizedsurface region 212 is to be formed. Examples of operating parameterswill now be provided with the understanding that the broad teachingsherein are not limited by such examples.

In a preferred embodiment, an air flow rate of between 20 and 200standard liter per minute (SLM) is used. In a more preferred embodiment,an air flow rate of between 50 and 150 SLM is used. In a most preferredembodiment, an air flow rate of between 75 and 125 SLM is used. In oneembodiment, an air flow rate of about 100 SLM is used.

In a preferred embodiment, a plasma power of between 0.3 kW and 5 kW isused. In a more preferred embodiment, a plasma power of between 1.2 and3.2 kW is used. In a most preferred embodiment, a plasma power ofbetween 1.7 and 2.7 kW is used. In one embodiment, a plasma power ofabout 2.2 kW is used.

In a preferred embodiment, a plasma power density per flow rate ofbetween 10 SLM/kW and 70 SLM/kW is used. In a more preferred embodiment,a plasma power per flow rate of between 25 SLM/kW and 55 SLM/kW is used.In a most preferred embodiment, a plasma power per flow rate of between35 SLM/kW and 45 SLM/kW is used. In one embodiment, a plasma power perflow rate of 100 SLM/2.5 kW=40 SLM/kW is used.

In a preferred embodiment, an electrode voltage of between 500V and4000V is used. In a more preferred embodiment, an electrode voltage ofbetween 1000V and 3000V is used. In a most preferred embodiment, anelectrode voltage of between 1000V and 1400V is used. In one embodiment,an electrode voltage of about 1200V is used.

In a preferred embodiment, a frequency of between direct current (DC)and 2540 MHz (i.e. 2.54 GHz) is used. In a more preferred embodiment, afrequency of between 50 kHz and 200 kHz is used. In a most preferredembodiment, a frequency between 100 kHz and 150 kHz is used. Aftercompletion of step 108, the method 100 continues to step 112.

At step 112, an article of manufacture (or product) 200 is positioned toreceive the non-thermal plasma stream 410. With attention to FIG. 2A,the (unworked or untreated) article 200 comprises a substrate 204, suchas a metal substrate, with an untreated upper surface 208. The untreatedupper surface 208 is the surface which will undergo treatment per themethod 100.

The substrate 204 of the article 200 may be configured with anycombination of the following parameters.

In a preferred embodiment, the substrate temperature is between −50 degC and +80 deg C. In a more preferred embodiment, the substratetemperature is between −20 deg C and +50 deg C. In a most preferredembodiment, the substrate temperature is +10 deg C and +30 deg C. In oneembodiment, the substrate temperature is about +20 deg C.

In another preferred embodiment, the substrate temperature may be ashigh as 0.95 imes the melting point of the surface that is beingtreated. For example, tin melts at 232C. The tin surface could be as hotas 220 C and still be in a solid state and accept a plasma treatment.

In another preferred embodiment, the substrate temperature may be as lowas absolute zero.

In a preferred embodiment, the air flow rate is between 5 SLM and 300SLM. In a more preferred embodiment, the air flow rate is between 10 SLMand 250 SLM. In a most preferred embodiment, the air flow rate isbetween 20 SLM and 200 SLM.

In a preferred embodiment, the substrate is descaled metal with a smoothsurface roughness of less than 10 mil. In a more preferred embodiment,the substrate is descaled metal with a smooth surface roughness of lessthan 5 mil. In a most preferred embodiment, the substrate is descaledmetal with a smooth surface roughness of less than 0.01 mil. In oneembodiment, the substrate is descaled metal with a smooth surfaceroughness of between 0.01 mil to 5 mil.

(It should be noted that the method of the disclosure generally works toenhance bonding on either atomically flat surfaces or jagged and roughsurfaces with, e.g. +/−3 cm roughness. An advantage is that whateversurface roughness is presented may be useable such that no secondaryprocess to create a specific roughness is required. Stated another way,one can use whatever roughness is provided and the method will improveadhesion.)

The substrate 204 may be, in one embodiment, any metal or metal alloy.In one embodiment, the substrate 204 is a composite material, a ceramic,and/or a semiconductor.

After completion of step 112, the method 100 continues to step 116.

At step 116, the untreated upper surface 208 of article 200 is treatedwith the non-thermal plasma stream 410. The non-thermal plasma stream410 energies the untreated upper surface 208 (of FIG. 2A) to increasethe surface energy of the untreated upper surface 208, creating anenergized surface region 212 with treated upper surface 220 (see FIG.2B). Stated another way, the non-thermal plasma stream 410 creates anenergized surface region 212 with higher dyne level than before thesurface treatment. The energized surface region 212 acts as an adhesionlayer and is disposed above or adjacent a bulk layer 216 of thesubstrate 204. After undergoing treatment by the non-thermal plasmastream, the article 200 comprises a treated upper surface 220. Thetreated upper surface 220 in effect replaces the untreated upper surface208 depicted in FIG. 2A. In one embodiment, the substrate 204 is a metalor metal alloy, the bulk layer 216 is a bulk metallic layer, theenergized surface region 212 is a metal oxide layer, and the treatedupper surface 220 is an outer oxide surface.

As briefly discussed above, in one embodiment, the non-thermal plasmastream 410 is provided by a plasma generating device 400 configured todischarge an atmospheric pressure plasma stream (or plasma “plume”) 410from a nozzle. In such an embodiment, the plasma generating device 400may be positioned at some specified distance between the nozzle and theuntreated upper surface 208 of the article 200, and oriented to directthe atmospheric pressure plasma stream 410 toward the surface 208 of thearticle 200. While the atmospheric pressure plasma stream 410 is active,the nozzle directing the atmospheric pressure plasma stream 410 devicemay be moved across the untreated upper surface 208 of the article 200.

Among other things, the non-thermal plasma stream 410 promotes orenhances the bonding of the surface 208 of the article 200 to a coating,such as an arc-spray coating or a thermal-spray coating. The non-thermalplasma stream 410 may be generated in close proximity to the substratesurface to ensure the surface is exposed to the non-thermal plasmastream 410 or at least the afterglow thereof. In some embodiments, thegenerated plasma may be transported toward the substrate surface by aflow of air, or additionally by an electric field, which may be theelectric field utilized to generate the plasma. The plasma is generatedunder conditions that, if desired, can produce a high concentration ofmonatomic oxygen in the plasma or other chemically reactive atomic ormolecular species. The plasma may also produce a high concentration ofhighly energetic and reactive singlet oxygen in the plasma or othersinglet species of various elements.

On some substrates, the plasma can be effectively directed toselectively oxidizing the substrate surface. In other cases, thenon-thermal plasma can be utilized to only alter the first few atomiclayers of a substrate, effectively just changing the chemical surfacegroups on the substrate' s surface.

In one embodiment the plasma forms an oxide layer of nanoscale thicknesson the metallic substrate to promote bonding. The plasma-formed oxidelayer may be grown from the base metal of the metallic substrate itselfand may therefore be permanently and rigidly attached to the substrate.Stated another way, in some embodiments, the oxide layer may becharacterized as being integral with the underlying bulk of the metallicsubstrate. The bulk of the metallic substrate may be characterized asthat part of the metallic substrate that is substantially free of themetal oxide formed as the overlying oxide laver.

Furthermore, the plasma-formed oxide layer, in some embodiments, isporous, may add a nanoscale surface texture and/or may increase thesurface area that is available for bonding to the coating (see steps 120and 124) as applied by the coating stream 510.

Note that, through the disclosed process, nanoscale roughness may beenhanced to increase (in particular, mechanical) bonding of thearc-spray or thermal-spray. In addition to any increase in nanoscaleroughness to promote mechanical bonding, the post plasma treated surfacepromotes stronger chemical bonds to the surface. The plasma works onatomically smooth surfaces because there is chemical bonding which canbe many times higher bond strength. The plasma can promote adhesion onatomically smooth surfaces because there is chemical bonding which canimpart higher bond strengths compared to strictly mechanical means.

Another effect of the application, or spraying, of the non-thermalplasma stream 410 to the untreated upper surface 208 of the article 200is to increase the surface energy of the newly formed plasma-oxidizedoxide layer (as compared to the surface energy of the original outersurface of the metallic substrate), which further enhances adhesion whena coating is applied to the surfaces within a certain period of time.

The non-thermal plasma stream 410, as generated by a plasma generatingdevice 400, may be operated with enriched gas mixtures which mayincrease the flux of oxygen or other desired chemical terminationsgroups onto the substrate. Different chemical groups may be chosen toenhance the adhesion for the specific chemistry of the substrate and thearc deposited material. For example, a plasma pen may be operated withnitrogen to produce atomic nitrogen species which may be used to nitridesurfaces or to from amine groups in the presence of hydrogen.

Furthermore, alternative gases may be used to terminate the surface suchas: N, 0, F, Cl, Br, CO2 (carbon dioxide) Ammonia, Water, and Hydrogen.

Also, depending on the type of arc-spray or thermal coating, it may bepreferred to use a chemical species other than oxygen to activate ametallic surface, e.g. a nitride may be used to bond with certainnitride forming alloy systems.

In one embodiment, a DBD plasma device may be used to activate thesurface but at relatively lower plasma densities and slower treatmenttimes. Alternatively, any atmospheric plasma device that produces enoughflux of energetic plasma species could be used to treat the untreatedupper surface 208 of the article 200. However, many atmospheric plasmasources that are used for surface treatment do not produce a significantflux of energetic species to enable an industrially feasible process tobe created.

The composition of an air plasma is a mixture of different components,including various charged and electronically excited species of oxygenand nitrogen, and other trace gases found in air. The plasma isgenerated under conditions that produce a high plasma density, which, ifdesired, can produce a high density of monatomic oxygen ions (and/orother monatomic oxygen species) in the plasma as well as chemicallyreactive singlet oxygen. In one embodiment, the density of ionizedspecies in the plasma is in a range from 1×10¹³ ions/cm³ to1×10^(‥)ions/cm³ , one specific yet non-exclusive example being about2.55×10¹⁶ ions/cm³.

As appreciated by persons skilled in the art, singlet oxygen is a highlyenergetic and chemically reactive form of diatomic oxygen (O₂), ascompared to the ground-state, or triplet, diatomic oxygen (O2) that is apredominant constituent of naturally occurring air. The monatomic oxygenhas a much higher diffusivity and chemical reactivity compared tomolecular oxygen species such as diatomic oxygen (O2) and ozone (O3),which may also be produced in the air plasma. As a result of theuntreated upper surface 208 of the article 200 being exposed to thisplasma, monatomic oxygen species penetrate the untreated upper surface208 of the article 200 and can combine with metal atoms of the metallicsubstrate 204 to form a metal oxide.n At other times the stand-offdistance from the substrate to be treated can be increased to eliminatethe monatomic oxygen from reaching the surface to provide a surfacetreatment that does not cause a surface oxide to form. Consequently, asillustrated in FIGS. 2A-C, a distinct energized surface region 212 isformed from a portion of the metallic substrate 204 and is rigidlyattached to the metallic substrate 204. In some cases, the metal oxidelayer 212 serves as a highly effective adhesion promoting layer to whicha coating may be applied (see step 124 and arc-spray 510).

In one embodiment, the treated upper surface 220 (which in this exampleis an outer oxide surface) is porous, or at least is superficiallyporous. Such nanoscale porosity may significantly increase the surfacearea of the outer oxide surface, thereby providing a significantlyincreased surface area for bonding and adherence to the arc-spraycoating, as compared to a nonporous or less rough surface. In oneembodiment, the treated upper surface 220 may not be generally porousand is a few atoms or molecules thick.

It should be noted it is beneficial to have an oxide layer for adhesiononly in certain material systems.

In the embodiment in which the substrate 204 is a metal or metal alloy,the bulk layer 216 is a bulk metallic layer, the energized surfaceregion 212 is a metal oxide layer, and the treated upper surface 220 isan outer oxide surface. In such an embodiment the plasma treatment mayprovide a surface treatment that changes the first few atomic ormolecular layers on the surface.

The non-thermal plasma stream 410 is directed toward the surface ofsubstrate at high velocities. In one embodiment, the non-thermal plasmastream 410 impacts the surface of the substrate at near or exceedingsonic velocities. Stated another way, in one embodiment the non-thermalplasma stream 410 impacts the surface of the substrate at a velocityfaster than the local environmental speed of sound.

After the treatment of the surface of the article 200 with thenon-thermal plasma stream 410, the treated upper surface 220 is moreamenable to adhesion of an arc-spray (or thermal) coating. One or moreprocesses occur to enable the heightened adhesion. For example, surfacemonolayers may be added to change chemical groups which promote adhesionto a substrate's base metallic material. Also, surface monolayers mayslightly alter to change surface chemical groups, thereby promotingadhesion to a substrate's base metallic material. Furthermore, plasmatreatment may etch organic residues onto the surface and leave thesurface nearly atomically clean. Also, energetic species from the plasmamay increase the surface energy of the metal surface and reduce thesurface tension, which promotes wetting of the surface by the liquidmetal produced by the arc spray apparatus. Also, the plasma surfacetreatment creates active chemical sites that can bond chemically withthe arc sprayed metal. Lastly, the high plasma density air plasmaproduces a high fluence of atomic oxygen which has a much higherdiffusivity compared to molecular oxygen species, such as O2 and O3,which allows rapid cleaning of any organic contaminants on the surface.

In one embodiment, the plasma treatment may be performed manually orrobotically with overlapping surface coverage to ensure completetreatment area coverage.

After completion of step 116, the method 100 continues to step 120.

At step 120, an arc-spray coating stream is generated. The arc-spraycoating stream is directed at the energized surface region 212, to formor create an arc-spray coating 240. Stated another way, the arc-spraycoating stream is directed at the energized surface region 224 andadheres or bonds an arc-spray coating to an upper surface of the article200.

The arc spray may also be a pure metal, a pure metal alloy, a cermet ora mixture of metal and inorganic particulates.

The arc-sprayed metal is sprayed in air and, in some embodiments,includes a sheath of air plasma surrounding the molten metal; thismolten metal surface is thus plasma treated as it is being propelledtowards the surface to be coated. When both plasma-treated surfaces meet(the molten droplets of metal and the plasma treated substrate), theenhanced chemical reactivity imparted by the air plasma treatmentenhances the bonding, creating a chemical as well as a mechanical bond.Because the bonding is now chemical and not just mechanical, strongadhesion can occur on relatively flat and smooth surfaces, doing awaywith the need for grit blasting, creation of surface roughness, orprofiling the surface in another step.

In a preferred embodiment, the arc-spray coating stream 510 (see step124) is applied within 60 minutes after the completion of spraying ofthe article with the non-thermal plasma stream 410 (i.e. within 60minutes after step 116.) In a more preferred embodiment, the arc-spraycoating stream 510 (see step 124) is applied within 40 minutes after thecompletion of spraying of the article with the non-thermal plasma stream410. In a most preferred embodiment, the arc-spray coating stream 510(see step 124) is applied within 30 minutes after the completion ofspraying of the article with the non-thermal plasma stream 410. Aftercompletion of step 120, the method 100 ends at step 128.

With reference to FIG. 2C, the energized surface region 212 is muchthinner in thickness than the arc-sprayed coating 240. Generally, theenergized surface region 212 is of thickness at the molecular level. Incontrast, the thickness of the arc-sprayed coating 240 may vary frommicron thickness to inches.

In a preferred embodiment, the arc-sprayed coating 240 is of thicknessbetween 10 micron to 2000 micron. In a more preferred embodiment, thearc-sprayed coating 240 is of thickness between 20 micron and 2000micron. In a most preferred embodiment, the arc-sprayed coating 240 isof thickness between 25 micron and 1000 micron. In one embodiment, thearc-sprayed coating 240 is of thickness of about 200 micron.

In another embodiment, the arc-sprayed coating 240 is of thickness ofmore than 12,700 micron (0.50 inch). In another embodiment, thearc-sprayed coating 240 is of thickness of more than 19,050 micron (0.75inch).

Several benefits ensue from the method 100 and system 300. The benefitsinclude: reduction in the steps required to prepare a surface forarc-spray bonding, vitiate the need to grit blast a surface to make aprofile or surface roughness, increase chemical bonding at the interfacebetween the arc splats and the surface instead of just a mechanicalbond, reduce the likelihood of user error by elimination of steps in aprocess, reduce process costs by reducing the time required to prep asurface before bonding, reduce process cost by eliminating chemicals andother materials required to prepare a surface. Also, the raw materialrequired for plasma (air) is infinitely renewable and always onavailable at any site in the world. Lastly, with some materials, e.g.titanium, there is a clear visual color change which provides a user anindication that plasma processing has been completed; in contrast, mostprocesses that involve multiple critical preparation steps are invisibleand thus may easily be skipped given a lack of visual indication.

It is noted that although FIG. 3 depicts the system 300 to promoteadhesion of a surface coating to an article comprising both a plasmagenerating device 400 and an arc-spray generating device 500 (or athermal spray generating device), these two components (400, 500) may beseparated, in one or both of time and physical proximity. Stated anotherway, the plasma generating device 400 may treat a surface of an articleat a first location, and the arc-spray generating device 500 may coatthe surface at a second location. The time between treatment of thesurface by the plasma generating device 400 and the coating by thearc-spray (or thermal spray) generating device 500 may be several hours,e.g. from 2-5 hours in one embodiment.

Also, the methods and devices of the disclosure may be applied toceramic surfaces, and inorganic composites, such as metallic matrixcomposites with embedded ceramic fibers and the like.

Furthermore, the arc-spray (or thermal spray) may be used to depositvaried materials onto varied surfaces, e.g. deposit ceramic on metal,metal on ceramic, cermet on metal, metal on ceramic, etc.

Examples of the processors as described herein may include, but are notlimited to, at least one of Qualcomm® Snapdragon® 800 and 801, Qualcomm®Snapdragon® 610 and 615 with 4G LTE Integration and 64-bit computing,Apple® A7 processor with 64-bit architecture, Apple® M7 motioncoprocessors, Samsung® Exynos® series, the Intel® Core™ family ofprocessors, the Intel® Xeon® family of processors, the Intel® Atom™family of processors, the Intel Itanium® family of processors, Intel®Core® i5-4670K and i7-4770K 22 nm Haswell, Intel® Core® i5-3570K 22 nmIvy Bridge, the AMD® FX™ family of processors, AMD® FX-4300, FX-6300,and FX-8350 32 nm Vishera, AMD® Kaveri processors, Texas Instruments®Jacinto C6000™ automotive infotainment processors, Texas Instruments®OMAP™ automotive-grade mobile processors, ARM® Cortex™-M processors,ARM® Cortex-A and ARM926EJ-S™ processors, other industry-equivalentprocessors, and may perform computational functions using any known orfuture-developed standard, instruction set, libraries, and/orarchitecture.

The exemplary systems and methods of this disclosure have been describedin relation to Promoting adhesion of coatings on surfaces, such aspromoting adhesion of arc-spray coatings onto surfaces such as metallicor ceramic surfaces with use of a non-thermal plasma stream atatmospheric pressure. However, to avoid unnecessarily obscuring thepresent disclosure, the preceding description omits a number of knownstructures and devices. This omission is not to be construed as alimitation of the scopes of the claims. Specific details are set forthto provide an understanding of the present disclosure. It should howeverbe appreciated that the present disclosure may be practiced in a varietyof ways beyond the specific detail set forth herein.

Furthermore, while the exemplary aspects, embodiments, and/orconfigurations illustrated herein show the various components of thesystem collocated, certain components of the system can be locatedremotely, at distant portions of a distributed network, such as a LANand/or the Internet, or within a dedicated system. Thus, it should beappreciated, that the components of the system can be combined in to oneor more devices or collocated on a particular node of a distributednetwork, such as an analog and/or digital telecommunications network, apacket-switch network, or a circuit-switched network. It will beappreciated from the preceding description, and for reasons ofcomputational efficiency, that the components of the system can bearranged at any location within a distributed network of componentswithout affecting the operation of the system. For example, the variouscomponents can be in a switch such as a PBX and media server, gateway,in one or more communications devices, at one or more users' premises,or some combination thereof. Similarly, one or more functional portionsof the system could be distributed between a telecommunicationsdevice(s) and an associated computing device.

Furthermore, it should be appreciated that the various links connectingthe elements can be wired or wireless links, or any combination thereof,or any other known or later developed element(s) that is capable ofsupplying and/or communicating data to and from the connected elements.These wired or wireless links can also be secure links and may becapable of communicating encrypted information. Transmission media usedas links, for example, can be any suitable carrier for electricalsignals, including coaxial cables, copper wire and fiber optics, and maytake the form of acoustic or light waves, such as those generated duringradio-wave and infra-red data communications.

Also, while the flowcharts have been discussed and illustrated inrelation to a particular sequence of events, it should be appreciatedthat changes, additions, and omissions to this sequence can occurwithout materially affecting the operation of the disclosed embodiments,configuration, and aspects.

A number of variations and modifications of the disclosure can be used.It would be possible to provide for some features of the disclosurewithout providing others.

In yet another embodiment, the systems and methods of this disclosurecan be implemented in conjunction with a special purpose computer, aprogrammed microprocessor or microcontroller and peripheral integratedcircuit element(s), an ASIC or other integrated circuit, a digitalsignal processor, a hard-wired electronic or logic circuit such asdiscrete element circuit, a programmable logic device or gate array suchas PLD, PLA, FPGA, PAL, special purpose computer, any comparable means,or the like. In general, any device(s) or means capable of implementingthe methodology illustrated herein can be used to implement the variousaspects of this disclosure. Exemplary hardware that can be used for thedisclosed embodiments, configurations and aspects includes computers,handheld devices, telephones (e.g., cellular, Internet enabled, digital,analog, hybrids, and others), and other hardware known in the art. Someof these devices include processors (e.g., a single or multiplemicroprocessors), memory, nonvolatile storage, input devices, and outputdevices. Furthermore, alternative software implementations including,but not limited to, distributed processing or component/objectdistributed processing, parallel processing, or virtual machineprocessing can also be constructed to implement the methods describedherein.

In yet another embodiment, the disclosed methods may be readilyimplemented in conjunction with software using object or object-orientedsoftware development environments that provide portable source code thatcan be used on a variety of computer or workstation platforms.Alternatively, the disclosed system may be implemented partially orfully in hardware using standard logic circuits or VLSI design. Whethersoftware or hardware is used to implement the systems in accordance withthis disclosure is dependent on the speed and/or efficiency requirementsof the system, the particular function, and the particular software orhardware systems or microprocessor or microcomputer systems beingutilized.

In yet another embodiment, the disclosed methods may be partiallyimplemented in software that can be stored on a storage medium, executedon programmed general-purpose computer with the cooperation of acontroller and memory, a special purpose computer, a microprocessor, orthe like. In these instances, the systems and methods of this disclosurecan be implemented as program embedded on personal computer such as anapplet, JAVA® or CGI script, as a resource residing on a server orcomputer workstation, as a routine embedded in a dedicated measurementsystem, system component, or the like. The system can also beimplemented by physically incorporating the system and/or method into asoftware and/or hardware system.

Although the present disclosure describes components and functionsimplemented in the aspects, embodiments, and/or configurations withreference to particular standards and protocols, the aspects,embodiments, and/or configurations are not limited to such standards andprotocols. Other similar standards and protocols not mentioned hereinare in existence and are included in the present disclosure. Moreover,the standards and protocols mentioned herein, and other similarstandards and protocols not mentioned herein are periodically supersededby faster or more effective equivalents having essentially the samefunctions. Such replacement standards and protocols having the samefunctions are considered equivalents included in the present disclosure.

The present disclosure, in various aspects, embodiments, and/orconfigurations, includes components, methods, processes, systems and/orapparatus substantially as depicted and described herein, includingvarious aspects, embodiments, configurations embodiments,sub-combinations, and/or subsets thereof. Those of skill in the art willunderstand how to make and use the disclosed aspects, embodiments,and/or configurations after understanding the present disclosure. Thepresent disclosure, in various aspects, embodiments, and/orconfigurations, includes providing devices and processes in the absenceof items not depicted and/or described herein or in various aspects,embodiments, and/or configurations hereof, including in the absence ofsuch items as may have been used in previous devices or processes, e.g.,for improving performance, achieving ease and\or reducing cost ofimplementation.

The foregoing discussion has been presented for purposes of illustrationand description. The foregoing is not intended to limit the disclosureto the form or forms disclosed herein. In the foregoing DetailedDescription for example, various features of the disclosure are groupedtogether in one or more aspects, embodiments, and/or configurations forstreamlining the disclosure. The features of the aspects, embodiments,and/or configurations of the disclosure may be combined in alternateaspects, embodiments, and/or configurations other than those discussedabove. This method of disclosure is not to be interpreted as reflectingan intention that the claims require more features than are expresslyrecited in each claim. Rather, as the following claims reflect,inventive aspects lie in less than all features of a single foregoingdisclosed aspect, embodiment, and/or configuration. Thus, the followingclaims are hereby incorporated into this Detailed Description, with eachclaim standing on its own as a separate preferred embodiment of thedisclosure.

Moreover, though the description has included description of one or moreaspects, embodiments, and/or configurations and certain variations andmodifications, other variations, combinations, and modifications arewithin the scope of the disclosure, e.g., as may be within the skill andknowledge of those in the art, after understanding the presentdisclosure. It is intended to obtain rights which include alternativeaspects, embodiments, and/or configurations to the extent permitted,including alternate, interchangeable and/or equivalent structures,functions, ranges or steps to those claimed, whether or not suchalternate, interchangeable and/or equivalent structures, functions,ranges or steps are disclosed herein, and without intending to publiclydedicate any patentable subject matter.

What is claimed is:
 1. A method to adhere an arc-spray coating to asurface of an article, the method comprising: generating a non-thermalplasma stream, the non-thermal plasma stream at atmospheric pressure;positioning the surface of the article to receive the non-thermal plasmastream; treating the surface of the article with the non-thermal plasmastream to create an energized surface region; generating an arc-spraycoating stream; directing the arc-spray coating stream at the energizedsurface region; wherein: the arc-spray coating stream forms an arc-spraycoating surface associated with the energized surface region of thearticle.
 2. The method of claim 1, wherein the energized surface regioncomprises etched organic residues.
 3. The method of claim 1, wherein thenon-thermal plasma stream comprises monatomic oxygen species.
 4. Themethod of claim 1, wherein the article is metallic and the surface is ametallic surface.
 5. The method of claim 4, wherein the energizedsurface region is a metal oxide region.
 6. The method of claim 5,wherein the metal oxide region comprises an outer oxide surface.
 7. Themethod of claim 6, wherein the arc-spray coating stream is directed atthe outer oxide region.
 8. The method of claim 1, wherein the article ismetallic, the surface comprises a metallic surface, and the arc-spraystream comprises a metal.
 9. The method of claim 8, further comprisingthe step of forming chemical bonding sites on the energized surfaceregion, the chemical bonding sites promoting chemical bonding with theenergized surface region.
 10. The method of claim 1, wherein the articleis metallic and the surface is a metallic surface.
 11. The method ofclaim 1, further comprising the step of applying an auxiliary gas ontothe surface of the article.
 12. The method of claim 1, wherein thenon-thermal plasma stream comprises monatomic nitrogen.
 13. The methodof claim 1, wherein the arc-spray coating stream is a metallic arc-spraycoating stream comprising a stream of projected molten metal surroundedby a sheath of air plasma.
 14. The method of claim 1, wherein thesurface is a metallic surface, and the non-thermal plasma streamcomprises an energetic species chemically reactive with the metallicsurface.
 15. The method of claim 1, further comprising the applicationof a gas curtain associated with the non-thermal plasma stream.
 16. Themethod of claim 1, wherein the arc-spray stream comprises a sheath ofair plasma.
 17. The method of claim 1, wherein the energized surfaceregion comprises etched inorganic residues.
 18. The method of claim 1,wherein the article is ceramic, the surface comprises a ceramic surface,and the arc-spray stream comprises a metal.
 19. The method of claim 1,wherein the article is ceramic, the surface comprises a ceramic surface,and the arc-spray stream comprises a cermet.
 20. The method of claim 1,wherein the article is ceramic, the surface comprises a ceramic surface,and the arc-spray stream comprises a ceramic.
 21. The method of claim 1,wherein the non-thermal plasma stream comprises monatomic chemicalspecies.
 22. The method of claim 1, wherein the non-thermal plasmastream comprises a tailored gas that forms a tailored chemical specieson the surface.
 23. The method of claim 22, wherein the tailored gas isammonia and the tailored chemical species comprise amine groups.
 24. Themethod of claim 22, wherein the tailored gas is water and the tailoredchemical species comprise hydroxyl groups.
 25. A method to bond anarc-spray coating to a metal surface of an article, the methodcomprising: generating a non-thermal plasma stream, the non-thermalplasma stream at atmospheric pressure and comprising monatomic oxygen;positioning the metal surface of the article to receive the non-thermalplasma stream; treating the metal surface of the article with thenon-thermal plasma stream to create a metal oxide region, the metaloxide region comprising an outer oxide surface and etched organicresidues; generating a metallic arc-spray coating stream comprising astream of projected molten metal surrounded by a sheath of air plasma;and directing the metallic arc-spray coating stream at the metal oxideregion; wherein: the molten metal bonds with the metal oxide region tobond the arc-spray coating to the metal surface of the article.
 26. Asystem to adhere an arc-spray coating to a surface of an article, thesystem comprising: a plasma generating device configured to generate anon-thermal plasma stream at atmospheric pressure; and an arc-spraygenerating device configured to generate an arc-spray coating stream;wherein: the non-thermal plasma stream is directed at the surface of thearticle to create an energized surface region; the arc-spray coatingstream is directed at the energized surface region; and the arc-spraycoating is adhered to the surface of the article.
 27. The system ofclaim 26, wherein the non-thermal plasma stream comprises monatomicoxygen, the article is metallic, the surface is a metallic surface, andthe arc-spray stream comprises a metal.
 28. The system of claim 27,wherein the non-thermal plasma generating device is configured to directan auxiliary gas onto the metallic surface, and the arc-spray coatingstream is a metallic arc-spray coating stream comprising a stream ofprojected molten metal surrounded by a sheath of air plasma.